Exclusion Principle - why doesn't degneracy balance weight?

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SUMMARY

The discussion centers on the Pauli Exclusion Principle (PEP) and its role in explaining why a chair breaks under excessive weight. In white dwarfs and neutron stars, gravity is countered by high outward pressure from fermions, which exhibit high velocities in confined spaces. However, in ordinary materials like a chair, the PEP does increase electron repulsion as they are compressed, but this repulsion is insufficient to counteract the net force exerted by heavy weights. Ultimately, the limited mass of electrons leads to structural failure when the applied force exceeds the PEP-induced repulsion.

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  • Understanding of the Pauli Exclusion Principle (PEP)
  • Basic knowledge of electron behavior in materials
  • Familiarity with concepts of force and structural integrity
  • Awareness of fermions and their properties in physics
NEXT STEPS
  • Research the implications of the Pauli Exclusion Principle in quantum mechanics
  • Study the mechanics of structural failure in materials under stress
  • Explore the behavior of fermions in astrophysical contexts, such as in neutron stars
  • Investigate the relationship between electron density and material strength
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Students of physics, material scientists, and engineers interested in the principles of structural integrity and quantum mechanics.

AlfaFoxtrot
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Fairly simple question, I just couldn't think of a suitable explanation for it.

In white dwarfs, neutron stars etc gravity is balanced by high outward pressure of fermions, which are in a confined space, so have v. high velocities. My question is, if you placed a heavy weight on an ordinary chair, it doesn't go straight through the chair because of the electrostatic repulsion of electrons, but also the PEP repulsion as they are being squeezed closer together. So why does a chair break when a weight too heavy is put on it? Surely the PEP repulsion just increases as electrons are moved closer together, thereby balancing the weight and not putting any stress on the chair?

I'm sure the explanation is dead simple, and I'm currently thinking it's a equal-opposite reaction kind of thing. Thanks in advance for any replies...
 
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The reason why a chair breaks when a weight too heavy is placed on it is because the electrons in the chair are not able to resist the pressure of the weight due to their limited mass. The Pauli Exclusion Principle (PEP) does increase the repulsive force between the electrons, but it is not enough to oppose the weight which produces a net force that is greater than the force of the PEP repulsion. This net force causes the chair to eventually break.
 

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